Snail Kite

Snail Kite

Rostrhamus sociabilis

The Snail Kite is a bird that relies on wetlands to forage for their main prey item: snails. This makes their migratory patterns especially interesting to Smithsonian scientists, who are tracking this species in South America.

Tracking

Although the Snail Kite is listed as “least concern” by the International Union for Conservation of Nature (IUCN), there is surprisingly little known about the South American population. As the name suggests, this species of kite feeds almost exclusively on snails, therefore inhabiting wetlands throughout most of the year. By tagging Snail Kites in Brazil, Smithsonian scientists and their Brazilian colleagues hope to answer questions such as: When and how fast do they migrate? Where do they spend the non-breeding season? What is the relationship between water quality/levels, snails and movements of a specialist snail feeder? In addition, there is a relatively well-studied population of Snail Kites that is found in Florida that can provide a point of comparison to the lesser-studied South American population.

Snail Kites that breed in southern Brazil may migrate north after the breeding season, spending the non-breeding season in the Pantanal (Antas 1994), one of the largest wetlands in the world. To describe these movement patterns, scientists are studying Snail Kites at Taim Ecological Station in southern Brazil. This protected area primarily consists of wetlands that host a large variety of plant and wildlife species. Verbail traps are used to capture the Snail Kites, which consists of an artificial perch on top of a monofilament noose attached to a spring. When a Snail Kite lands on the perch, it releases the spring, closing the noose around the kite's feet. The kite is quickly removed from the trap, measured, and tagged with a satellite transmitter before being released. These satellite transmitters send us the position of each kite every two days for several years. One of the kites visited four countries (Brazil, Uruguay, Argentina, and Paraguay) in the first two weeks after being tagged, giving us new insights into the high mobility of these birds. Smithsonian scientists are excited about the potential for these tags to provide interesting data about the movements of Snail Kites and other poorly understood migratory birds in South America.

Resources

Scholarly Articles

Antas, P.D.T.Z., 1994. Migration and other movements among the lower Paraná River valley wetlands, Argentina, and the south Brazil/Pantanal wetlands. Bird Conservation International, 4(2-3), pp.181-190.